Before anyone cries racism, no that's not it. Some very talented people from overseas in this company.
The problem is that Fiserv are abusing the H1-B system to supress wages across the board and build itself an extremely compliant workforce. Their visa is dependent on them keeping their job. Fiserv knows they can underpay and take advantage of people who won't (can't) speak up about it. It's bad for both Americans and H1-B holders.
I know this widespread in tech, but I've been to a few of these companies and I've never seen a company abuse the system as much as Fiserv do.